Ensure Replication Tests do not use a stale token

Fixed the replication tests to re-authenticate the common test dbaas
client in order to ensure that we do not use a stale auth_token when
running the replication tests.

Change-Id: I37a2a4b7dca056e84b48c66cbe3b8c8fb6a2f1db
Closes-bug: 1394831
Merge "Ensure Replication Tests do not use a stale token"